Electrical connector

ABSTRACT

An electrical connector employing a radially resistant barrel socket having a bore extending from one end which slidably receives an electrically conductive pin. A spacer member is disposed to space a stop member from the one end of the barrel socket. An inner diameter of a bore in the spacer member is greater than the inner diameter of the adjacent bores in the stop member and the barrel socket to define a recess which receives a projection carried on the pin which the pin is inserted into the barrel socket. An end cap is fixed over the stop member and the spacer member and to the barrel socket to resist axially outward flexure of an inner edge portion of the stop member upon the exertion of pull-out forces on the pin and the barrel socket tending to disengage the pin from the barrel socket.

BACKGROUND

[0001] The present invention relates, in general, to electricalconnectors and, more specifically, to radially resilient electricalsockets, also referred to as barrel terminals, in which a cylindricalelectrical prong or pin is axially inserted into a socket whose interiorsurface is defined by a plurality of contact strips or wires which arebent into a hyperbolic, radially inward extending shape by angularlyoffset strip ends.

[0002] Radially resilient electrical sockets or barrel terminals are awell known type of electrical connector as shown in U.S. Pat. Nos.4,657,335 and 4,734,063.

[0003] In such electrical sockets or barrel terminals, a generallyrectangular stamping is formed with two transversely extending websspaced inwardly from and parallel to opposite end edges of the sheet.Between the inner side edges of the transverse web, a plurality ofuniformly spaced, parallel slots are formed to define a plurality ofuniformly spaced, parallel, longitudinally extending strips which arejoined at opposite ends to the inward side edges of both transversewebs. Other longitudinally extending slots are coaxially formed in thesheet and extend inwardly from the end edges of the blank to the outerside edges of the transverse webs to form a plurality of uniformlyspaced, longitudinally extending tabs projecting outwardly from eachtransverse web.

[0004] The blank or sheet is then formed into a cylinder with thelongitudinal strips extending parallel to the axis of the nowcylindrical sheet. A closely fitting cylindrical sleeve is slippedcoaxially around the outer periphery of the cylindrical blank, andextends axially substantially between the outer edges of the transversewebs. The mounting tabs at each end of the blank are then bent outwardlyacross end edges of the sleeve into radially extending relationship tothe sleeve.

[0005] A relatively tight-fitting annular collar or outer barrel is thenaxially advanced against the radially projecting tabs at one end of thesleeve and slipped over the one end of the sleeve driving the tabs atthat end of the sleeve downwardly into face-to-face engagement with theouter surface of the one end of the sleeve. The fit of the annularcollar to the sleeve is chosen so that the end of the cylindrical blankat which the collar is located is fixedly clamped to the sleeve againstboth axial or rotary movement relative to the sleeve.

[0006] A tool typically having an annular array of uniformly spaced,axially projecting teeth is then engaged with the radially projectingtabs at the opposite end of the sleeve. The teeth on the tool arelocated to project axially between the radially projecting tabs closelyadjacent to the outer surface of the cylindrical sleeve. The tool isthen rotated about the longitudinal axis of the cylindrical sleeve whilethe sleeve is held stationary to rotatably displace the engaged tabsapproximately 15° to 45° from their original rotative orientationrelative to the sleeve and the bent over tabs at the opposite end of thesleeve. The tool is then withdrawn and a second annular collar or outerbarrel is force fitted over the tabs and the sleeve to fixedly locatethe opposite end of the blank in a rotatably offset position establishedby the tool.

[0007] When completed, such an electrical socket has longitudinal stripsextending generally along a straight line between the angularly offsetlocations adjacent the opposite ends of the cylindrical sleeve. Theinternal envelope cooperatively defined by the longitudinal strips is asurface of revolution coaxial to the axis of the cylindrical sleevehaving equal maximum radii at the points where the strips are joined tothe respective webs and a somewhat smaller radius midway of the lengthof the strips. The minimum radius, midway between the opposite ends ofthe strips, is selected to be slightly less than the radius of acylindrical connector pin which is to be inserted into the barrel socketso that the insertion of the pin requires the individual longitudinalstrips to stretch slightly longitudinally to firmly frictionally gripthe pin when it is seated within the barrel socket.

[0008] To put it another way, because of the angular offset orientationof the opposed ends of each of the strips, each strip is spaced from theinner wall of the sleeve in a radial direction progressively reaching amaximum radial spacing with respect to the outer sleeve midway betweenthe ends of the sleeve.

[0009] Such a radially resilient electrical barrel socket provides aneffective electrical connector which provides secure engagement with aninsertable pin; while still enabling easy manual withdrawal or insertionof the pin relative to the socket. Such connectors also provide a largeelectrical contact area between the pin and the socket which enablessuch connectors to be employed in high current applications.

[0010] It is also known to construct such an electrical connector in amanner in which one of the collars is formed as an integral part orextension of a support member forming a part of the overall connector.The afore-described assembly process remains the same except that theseparate collars at both ends of the socket are replaced by one collarat one end and a hollow, cylindrical extension of a connector which canbe inserted into or otherwise electrically connected to an electricaldevice, such as a vehicle alternator, etc. The hollow cylindrical end ofthe support receives and holds the tabs at the first end of the sleevetight against rotation while the opposing tabs are angularly rotated. Acollar or end cap is then clamped over the rotated tabs to maintain suchtabs in the rotated position.

[0011] Such radially resistant sockets are adapted for receivinggenerally cylindrical pins or terminals which are slid into the open endof the bore extending through the contact into forced engagement withthe hyperbolically shaped contact grid contact strips. The pin displacesthe hyperbolically shaped strips which generates a holding force toretain the pin in the socket or barrel terminal under a predeterminedretention or pull-out force resistance.

[0012] Also known in the connector art are detent mechanisms employed onthe pin and socket to increase the pull-out force resistance holding thepin in the socket. Such a detent mechanism typically employs a radiallyinward extending projection on one or more of the grid strips whichengages an annular recess formed in the pin. This detent not only formsa detectable insertion stop for the pin into the electrical socket; but,also, increases the pull-out force resistance due to the mechanical andfriction engagement between the grid contact projection(s) and theannular recess in the pin.

[0013] However, such detent mechanisms provide only a predeterminedamount of pull-out force resistance. Certain electrical connectorapplications may desirably require increased pull-out force resistancemagnitudes.

[0014] Thus, it would be desirable to provide an electrical connectoremploying a radially resistant electrical socket which has increasedpull-out force resistance with minimal modification to the socketdesign. It would also be desirable to provide such an electricalconnector in which the pull-out force resistance can be easily varied tosuit various application requirements.

SUMMARY

[0015] In one aspect of the present invention, an electrical connectoris disclosed as including a radially resilient barrel socket having abore with a first inner diameter extending from a first end. A stopmember has a bore with a second inner diameter at least as large as thefirst diameter of the bore in the barrel socket. Means are provided forspacing the stop member from the one end of the barrel socket anddefining a recess between the second inner diameter of the bore in thestop member and the one end of the barrel socket. The recess has a thirdinner diameter greater than the second inner diameter and the one end ofthe bore in the barrel socket. Means are provided for fixing the stopmember and the spacing means with respect to the one end of the barrelsocket. An electrically conductive member having an end pin isinsertable through the fixing means, the spacing means and the stopmember into the bore in the barrel socket. At least one projection iscarried on the pin. The at least one projection is insertable throughthe inner diameter of a bore formed in the fixing means into the recessdefined by the spacing means. An inner edge of the bore in the fixingmeans and an inner edge of the bore in the spacing means resistingmovement of the at least one projection on the pin axially outward fromthe one end of the barrel socket up to a predetermined pull-out force.

[0016] In another aspect, the spacing means is a spacer member having abore with the third inner diameter. The third inner diameter is largerthan the second inner diameter of the stop member and the first innerdiameter of the bore in the barrel socket. The recess is formed radiallyinward of the third inner diameter of the spacer member.

[0017] In another aspect, the fixing means includes an end cap having asidewall and an end wall. A bore is formed in the end wall of an innerdiameter sized to allow free passage of the at least one projectiontherethrough. An inner edge of the end wall surrounding the innerdiameter of the bore is disposed adjacent to an inner edge of thespacing means surrounding the bore in the spacing means to resistaxially outward flexure of the inner edge of the spacing means forcesare exerted on the pin and the connector tending to move the pin ismoved in an axially outward direction relative to the one end of thebarrel socket. The end cap is preferably fixedly mounted on the barrelsocket.

[0018] In one aspect, the at least one projection includes a singlecontinuous, annular projection on the pin.

[0019] In another aspect, the spacing means has an inner edgesurrounding the bore in the spacing means which is capable of axialflexure on insertion of the projection on the pin therethrough to allowpassage of the projection into the recess. The fixing means and thespacing means resist flexure of the inner edge of the spacing means inan axial direction away from the one end of the barrel socket in adirection tending to separate the pin from the barrel socket.

[0020] The electrical connector according to the present inventionuniquely provides different insertion or push-in force levels andpull-out force levels with the same connector structure. Withoutmodification to an existing resilient barrel socket contact, theaddition of a few additional components provides for a comparatively lowpush-in insertion force to trap a projection on an end pin portion of anelectrically conductive end form in a recess formed at one end of theelectrical connector. Pull-out movement of the projection and the endform from the barrel socket contact is resisted up to a comparativelyhigh pull-out force level to resist separation of the conductive memberfrom the connector body.

[0021] The inventive electrical connector employs a radially resilientelectrical socket of many different configurations which is providedwith a pull-out force resistance means to enable the pull-out forceresistance of a pin insertable into the electrical socket to beincreased to higher magnitudes as well as being able to be variablyselected to suit different application requirements. This increasedpull-out force resistance is achieved with few, if any, modifications tothe electrical socket structure.

BRIEF DESCRIPTION OF THE DRAWING

[0022] The various features, advantages and other uses of the presentinvention will become more apparent by referring to the followingdetailed description and drawing in which:

[0023]FIG. 1 is a plan view of a flat sheet metal blank employed inconstructing a barrel terminal for use in the present invention;

[0024]FIG. 2 is a side elevational view of the blank of FIG. 1 formedinto a cylinder;

[0025]FIG. 3 is a perspective view showing a close fitting cylindricalsleeve disposed about the blank of FIG. 2;

[0026]FIG. 4 is a perspective view of a subsequent step in theconstruction of the barrel terminal;

[0027]FIG. 5 is an enlarged side elevational, cross-sectional viewshowing a subsequent step in the construction method;

[0028]FIG. 6 is an enlarged side elevational, cross-sectional viewshowing yet another step in the construction method;

[0029]FIG. 7 is a perspective view depicting another step in theconstruction method;

[0030]FIG. 8 is a side elevational, longitudinal cross-sectional view ofthe final assembled state of the barrel terminal;

[0031]FIG. 9 is a longitudinal cross-sectional view of another aspect ofa connector and a barrel terminal useable in the present invention;

[0032]FIG. 10 is a partial, longitudinal cross-sectional view of oneaspect of an external grid anchor for the barrel terminal shown in FIG.9;

[0033]FIG. 11 is a partial, longitudinal cross-sectional view of anotheraspect of an external grid anchor for the barrel terminal shown in FIG.9;

[0034]FIG. 12 is a partial, longitudinal cross-sectional view showinganother aspect of an external grid anchor;

[0035]FIGS. 13 and 14 are partial, enlarged, longitudinalcross-sectional views showing another aspect of an internal anchor in apartially assembled and completely assembled state, respectively;

[0036]FIGS. 15 and 16 are partial, enlarged, longitudinalcross-sectional views showing another aspect of an internal anchor in apartially assembled and completely assembled state, respectively;

[0037] FIGS. 17-20 depict sequential steps in an alternate constructionmethod of another aspect of a barrel socket;

[0038]FIG. 21 is an exploded, partially cross section, side elevationalview of the completed electrical connector constructed according to themethod of FIGS. 21-24 shown in an interconnected use position.

[0039] FIGS. 22-24 depict sequential steps in the construction methodfor an alternate barrel socket;

[0040]FIG. 25 is a perspective view showing multiple means for fixedlymounting the tabs of the contactor to the sleeve;

[0041]FIG. 26 is a perspective view of another aspect of an electricalconnector;

[0042]FIG. 27 is a longitudinal, cross-sectional view of an electricalconnector shown in FIG. 26, with the grid inserted into the sleeve, butbefore the angular offset as applied to the grid strips;

[0043]FIGS. 28 and 29 are partial, enlarged, longitudinalcross-sectional views showing another aspect of an internal anchor shownin partially assembled and completely assembled states, respectively;

[0044]FIGS. 30 and 31 are partial, enlarged, longitudinalcross-sectional views showing another aspect of an internal anchor shownin partially assembled and completely assembled states, respectively;

[0045]FIGS. 32 and 33 are partial, enlarged, longitudinalcross-sectional views showing another aspect of an internal anchor inpartially assembled and completely assembled states, respectively;

[0046]FIGS. 34 and 35 are partial, enlarged, longitudinalcross-sectional views showing another aspect of an internal anchor inpartially assembled and completely assembled states, respectively;

[0047]FIG. 36 is a partial, enlarged, longitudinal cross-sectional viewshowing another aspect of an internal anchor;

[0048]FIG. 37 is a perspective view of an electrical connectorconstructed in accordance with the teachings of the present invention;

[0049]FIG. 38 is a cross-sectional view generally taken along lines38-38 in FIG. 39;

[0050]FIG. 39 is an exploded, side elevational view, similar to FIG. 40,but showing the components of the electrical connector of the presentinvention in a partially assembled state; and

[0051]FIG. 40 is an enlarged, side elevational view of the electricalconnector shown in FIG. 39, depicted in a latched state.

DETAILED DESCRIPTION

[0052] An electrical connector employs a radially resilient electricalcontact or socket having hyperbolically shaped contact strips or wires,a holder which receives at least a portion of the socket, hereafterreferred to as a “barrel socket or terminal”, and a conductive end formwhich is slidably inserted into the barrel socket to complete anelectrical circuit between circuit elements connected to or carried bythe end form and circuit elements connected to or carried by the holderin which the barrel socket is mounted.

[0053] The structure of a barrel socket used in an electrical connectoraccording to one aspect of the present invention is best explained by adescription of the manner in which it is manufactured.

[0054] The first step in the manufacture of the barrel socket is thestamping of a blank in the form shown in FIG. 1 from a flat piece ofsheet metal which preferably is a beryllium copper alloy which has bothmechanical and electrical properties well adapted for an electricalconnector application.

[0055] Referring to FIG. 1, the blank designated generally 20 is stampedin a generally rectangular configuration and formed with a pair ofspaced, parallel, transversely extending connecting web portions 22which are integrally connected to each other by a plurality of uniformlyspaced, parallel, longitudinally extending strips 24 which extendbetween the respective inner edges of the webs 22. A plurality ofspaced, parallel tabs 26 project longitudinally outwardly from the outeredges of the respective transverse webs 22.

[0056] The second step in the manufacturing process is shown in FIG. 2and finds the blank 20 formed into a horizontal, cylindrical, tubularconfiguration, the axis of the cylindrical tube extending parallel tothe longitudinal strips 24 and tabs 26.

[0057] After the blank 20 is formed into the cylindrical tubularconfiguration of FIG. 2, a close-fitting cylindrical sleeve 28 isslipped over the cylindrical tube as shown in FIG. 3, the axial lengthof sleeve 28 being sufficient to extend over both of transverse webs 22leaving the tabs 26 projecting outwardly from the opposite ends ofsleeve 28.

[0058] In the next step shown in FIG. 4, the projecting tabs 26 areflared or bent outwardly across one end edge of sleeve 28 to projectradially outwardly of the axis of the sleeve.

[0059] In the next step of the process shown in FIG. 5, a temporaryfirst housing or fixture 30 has a central bore 32 extending at leastfrom a first end 34 to an opposite end 36. The bore 32 has a diameterlarger than the diameter of the cylindrical sleeve 28 by a distanceequal to the thickness of the tabs 26. The first housing 30 is axiallydriven over one end of the sleeve 28 or the sleeve 28 is axially driveninto one of the first and second ends 34 and 36 of the first housing 30.The forcible interconnection of the sleeve 28 and the first housing 30bends the radially flared tabs 26 at the one end of the sleeve 28 backon themselves into overlapping, face-to-face relationship with the outersurface of the sleeve 28. The inner diameter of the bore 32 is chosensuch that when the first housing 30 and the first end of the blank 20and the sleeve 28 are in the position shown in FIG. 5, the first housing30 exerts sufficient force on the tabs 26 to clamp the tabs 26 againstthe outer surface of the sleeve 28 to prevent any axial or rotarymovement of the tabs 26 relative to the sleeve 28.

[0060] Next, as shown in FIG. 6, the tabs 26 at the opposite end of thesleeve 28 are flared or bent radially outwardly across the opposite endedge of the sleeve 28 to project radially outward from the axis of thesleeve 28.

[0061] In the next step shown in FIG. 7, a tubular tool 50 havinguniformly spaced, axially projecting teeth 52 on one end is engaged withthe radially projecting tabs 26 projecting out of one end of the sleeve28. The internal diameter of the tool 50 is such that it will have aloose, sliding fit with the outer diameter of the sleeve 28 and theteeth 52 are so spaced from each other so as to project through thespaces between the adjacent, radially projecting tabs 26.

[0062] When the tool 50 is seated with the teeth 52 between the radiallyprojecting tabs 26, the first housing 30 is clamped or otherwise heldagainst rotation and the tool 50 rotated coaxially of the sleeve 28through a predetermined angle, which is typically from about 15° toabout 45°. This action of the tool 50 rotatably offsets one end of theblank or sheet 20 from the previously fixed end held against rotation bythe first housing 30 relative to the sleeve 28. The characteristics ofthe beryllium copper alloy of which the blank or sheet 20 is preferablymade is such that, although the material possesses some resiliency, therotation imparted by the tool 50 permanently sets the blank 20 in therotated position.

[0063] Next, as shown in FIG. 8, a second housing 40 also having athrough bore 42 extending from a first end 44 to an opposed second end46 is axially driven over the sleeve 28 into interference with theradially outward extending tabs 26 or the ends of the sleeve 28 and theblank 20 extending outward from the first housing 30 are axially driveninto the bore 42 in the second housing 40. The second housing 42 is thenadvanced relative to the first housing 30 to force fit the interiorsurfaces of the bore 42 in the second housing 40 into engagement withthe radially extending, angularly offset tabs 26 thereby bending thetabs 26 over into face-to-face engagement with the outer surface of theother end of the sleeve 28.

[0064] The second housing 40 and the first housing 30 are advancedrelative to one another into near abutment to hold the angularly offsettabs 26 at each end of the sleeve 28 non-movably against the outersurface of the sleeve 28.

[0065] However, the above-described barrel socket or terminal hasopposed open ends allowing access to the tabs 26 on the blank or grid 20from either end to perform the above-described bending, inserting andlocking operations.

[0066] According to one aspect of a barrel terminal useable in thepresent connector and shown in FIG. 9, a modified barrel terminal ismounted in a terminal housing 60 having a barrel terminal receivingportion or body 62 and a contiguous, generally axially or angularlyspaced conductor or pin receiving portion 64. Thus, although the barrelterminal receiving portion or housing 62 is shown axially aligned withpin or conductor receiving portion or body 64, it will be understoodthat the two body portions 62 and 64, while contiguous or connected, canbe disposed at any angular orientation, such as a 45°, 90°, etc.

[0067] The barrel terminal receiving portion or body 62 has a first openend 66 which is hereafter defined as a“first or external end”. A bore 68extends from the first external end 66 to an internal wall 70, hereafteralso referred to as a “blind end”.

[0068] The pin receiving body 64 likewise has a first open end 72 and athrough bore 74 extending from the first open end 72 to an internal wall76. The bore 74 is configured for receiving a pin or conductor in anelectrical connection.

[0069] In addition, the pin receiving body 64 can also be configured aspart of an electrical use device, such as a battery wherein the body 64is formed as an integral part of the battery within an internalelectrical connection made by appropriate means to the body 64.

[0070] The terminal housing 60 shown in FIG. 9 can be produced fromeither stamped parts formed from flat metal stock and then formed intothe desired cylindrical configuration or machined from metal bar stock.

[0071] A barrel terminal 80 constructed according to any one of severaldifferent methodologies is mountable in the bore 68 of the barrelterminal body 62. As described in greater detail hereafter, the barrelterminal 80 is formed of a stamped grid having webs 82 and 84 atopposite ends of a plurality of interconnecting strips 86. Tabs 88extend oppositely from the webs 82 and 84, respectively, and are securedin place to the barrel terminal body 62 by external end anchors andinternal end anchors described hereafter, After the strips 86 have beenangularly offset from end to end to dispose each strip in a hyperbolicshape from end to end having a smaller internal diameter at a generallycenter point than the nominal, non-hyperbolic state of the strips 82.This diameter is typically smaller than the outer diameter of a pin orconductor inserted into the barrel terminal 80 so as to provide a secureelectrical contact between the barrel terminal and the inserted pin aswell as a high pin pull-out retention force.

[0072] Alternately, the strips 86 of the barrel terminal 80 can bereplaced by individual wires which are initially held in place by narrowneck portions or ribs between opposite ends of the wires which areseparated during the hyperbolic angular offset process. The ends of eachof the wires then act as the tabs for securement to the barrel terminalbody 62 by the external and internal anchors described hereafter. Such awire arrangement will also be understood to constitute a “grid” as theterm is used herein. As also described hereafter, several aspects of thebarrel terminal 80 may not require tabs at either the external orinternal end of the barrel terminal 80.

[0073] Referring now to FIGS. 17-21, there are depicted the constructionsteps according to another aspect of a method for manufacturing anelectrical connector utilizing a radially resilient socket.

[0074] In FIG. 17, the sleeve 28 is depicted. This construction stage issimilar to that described above and shown in FIG. 4 in which the blank20 has been bent or formed into a cylinder and the outer sleeve 28disposed closely there over with the tabs 26 projecting outward fromopposite ends of the sleeve 28 as shown in FIG. 3. However, in thismethod, the tabs 26 at both ends of the sleeve 28 are bent or foldedaround the outer ends of the sleeve 28 and back over the outer surfaceof the sleeve 28 to form a cartridge 29.

[0075] The first end 150 of the cartridge 29 is then inserted into afirst housing or fixture 152 having a bore 154, as shown in FIG. 18. Theinner diameter of the bore 154 is sized slightly larger than the outerdiameter of the sleeve 28 by a distance equal to the thickness of thetabs 26 so as to closely fold over the tabs 26 into face-to-faceengagement with the outer surface of the sleeve 28 when the first end150 of the cartridge 29 is inserted into the first housing 152. Itshould be noted that the cartridge 29 is only partially inserted intothe bore 154 in the first housing 152 such that the second end 156 ofthe sleeve 28 projects outwardly from the first housing 152 along withthe tabs 26 at the second end 156 of the sleeve 28.

[0076] The first end 150 of the cartridge 29 is inserted into the bore154 in the first housing 152 until the first end 150 engages one end ofa rotatable tool 158 which is rotatably and axially movably disposedwithin the bore 154. The tool 158 can be similar to the tool 50described above and shown in FIG. 7 and has teeth which engage thespaces between adjacent folded over tabs 26 at the first end 150 of thesleeve 28.

[0077] Next, as shown in FIG. 19, the second end 156 of the cartridge 29is inserted into or otherwise brought into engagement with a bore 160 ina cylindrical portion 162 of a terminal, holder, support or electricaldevice, all referred to generally hereafter as a holder 164. Thecylindrical portion 162 is disposed at one end of a support or base 166,the opposite end of which, by example only, includes an aperture 168 forreceiving a fastener 170, shown in FIG. 21, to secure another terminal172 carrying an electrical conductor, again by example only, to theholder 164.

[0078] The bore 160 in the cylindrical portion 162 can be divided intotwo sections, namely, a first end section 174 and a second end section176. The inner diameter of the first end section 174 is selected tocreate a press or interference fit with the tabs 26 at the second end156 of the cartridge 29 when the second end 156 of the cartridge 29 isinserted into the bore 160. The second end section 176 of the bore 160has a larger diameter than the first end section 174 to enable thesecond end 156 and the folded tabs 26 on the outer sleeve 28 to passfreely there through into pressfit engagement with the first end section174 of the bore 160. This forcibly mounts the second end 156 of thecartridge 29 in the cylindrical portion 162 of the holder 164 and bringsthe tabs 26 at the second end 156 of the outer sleeve 28 into secureelectrical contact with the inner surface of the bore 160.

[0079] The cartridge 29 is forcible inserted into the bore 160 until theentire outer sleeve and folded over tabs 26 at the first end 150 of thecartridge 29 are fully enclosed within the bore 160 as shown in FIG. 20.

[0080] As described above, the second end section 176 of the bore 160has a larger inner diameter than the adjacent first end section 174.This can be formed in a number of constructions, including a gradualdecreasing diameter taper along the length of the bore 160 from thefirst end section 176 to the second end section 178. Alternately, a stepmay be formed intermediate the ends of the cylindrical portion 162 toform two different diameter sections, one for the first end section 174and the other for the second end section 176 of the bore 160.

[0081] As shown in FIG. 20, when the cartridge 29 is fully inserted intothe bore 160, the second end 156 of the cartridge 29 and the folded overtabs 26 carried on the second end 156 are in a press-fit engagement withthe inner surfaces of the cylindrical portion 162 surrounding the bore160. However, the tabs 26 at the opposite end of the cartridge 29 willonly be loosely disposed between the inner surfaces of the second endsection 176 of the bore 160 and the adjacent outer surface of the sleeve28.

[0082] The rotatable tool 158 can be advanced by a suitable drivesource, such as a pressurized fluid cylinder, electric motor drive,etc., to slidably urge the first end 150 of the cartridge 29 and thefolded over tabs 26 carried thereon from the first housing 156 into thebore 160 in the cylindrical portion 162 of the holder 164.

[0083] Next, as shown by the arrow in FIG. 20, the rotatable tool 158 isrotated to angularly offset the tabs 26 at the first end 150 of thecartridge 29 from the corresponding tabs 26 at the second end 156 of thecartridge 29. This provides the desired hyperbolic shape to the strips24 between the webs 22 on the cylindrical blank as described above. Withthe rotatable tool 158 is held in the rotated position, the end portionof the cylindrical portion 162 of the holder 164 surrounding the secondend section 176 of the bore 160 is subjected to a swaging operationwhich deforms the end portion of the cylindrical portion 162 anddecreases its inner diameter to bring the inner diameter of the endportion of the cylindrical portion 162 into tight, close fittingengagement over the tabs 26 at the first end 150 of the outer sleeve 28so that the tabs 26 are tightly held between and in contact with theouter surface of the sleeve 28 and the inner surface of the bore 160.The rotatable tool 158 is then withdrawn along with the first housing152 leaving the completed connector denoted by reference number 180 inFIG. 21.

[0084] As shown in FIG. 21, a terminal 172 carrying an electricalconductor 173 may be securely attached to the aperture 168 in thesupport 166 of the holder 164 by means of a threaded fastener or screw170. Alternately, the holder 166 and the terminal 172 can be a unitaryone piece member like the holder 62. An elongated, cylindrical pin 182may be releasably inserted into the interior of the barrel socket 184 tocouple the electrical device or circuit to which the pin 182 is attachedwith the circuit or conductors or electrical device to which theconductor 173 and terminal 172 are connected via the socket 184 and theholder 164.

[0085] In yet another method, the bore 160 is smooth, but sized for apress fit with the tabs 26. The cartridge 29 initially is inserted halfway into the bore 160. Next, the tool 158 is rotated 15° to 45° tooffset the tabs 26 and one end of the internal strips from the opposedtabs and the opposite end of the strips. The tool 158 then axiallyadvances pushing the cartridge 29 fully into the bore 160 whereby thetabs 26 at both ends of the cartridge 29 are held in the angularlyoffset position through a press fit with the inner surface of the bore160.

[0086] An alternate method of constructing the blank 20 and outer sleeve28 described above and shown in FIGS. 1-4 as a unitary, one piece memberis depicted in FIGS. 23-25.

[0087] In this aspect, a one piece sheet metal blank 184 is formed witha first generally rectangular, solid end portion 186 and a plurality ofelongated, generally flat strips 188 which extend longitudinally fromone end of the solid end portion 186 and are equally spaced apart anddisposed in parallel. The entire blank 184 may be formed of a suitableelectrically conductive material, such as beryllium copper. The strips188 are unitarily joined to one end of the solid end portion 186 at afirst end 190 by welding or as a unitary stamping with the solid portion186. Alternately, the strips 188 maybe joined to the blank 186 alonglines 191 or 193 with suitably formed end portions on the strips 188 orthe blank 186.

[0088] Next, all of the strips 188 are bent or folded over the secondend 195 of the solid end portion 186 about the first end 190 and remainin parallel as shown in FIG. 24. As shown therein, the free ends 192 ofeach of the strips 188 extend beyond a first end 194 of the solid endportion 186. The portion of the strips 188 projecting beyond the firstend 194 form tabs 196.

[0089] Next, as shown in FIG. 25, the solid end portion 186 is thenfolded into a cylindrical sleeve 198 and the edges welded or otherwisefixedly joined together. The folding operation carries the strips 188overlaying one surface of the solid end portion 186 such that the strips188 are now disposed within the interior of the resulting cylindricalsleeve 198 as shown in FIG. 25. The tabs 196 still project outwardbeyond the first end 194 of the sleeve 198.

[0090] At this point in the construction of the sleeve 198, the secondend 195 may be inserted into tight engagement with a bore in a holder,as described above. The tabs 196 may be folded over the outer surface ofthe sleeve 198 and secured in the bore of a holder as described aboveand shown in FIG. 9, after the angular offset is imparted to one end ofthe strips 188, by either of the previously described constructionmethods.

[0091]FIG. 22 depicts three different attachment locations or methodsfor attaching the tabs 196 or an end portion of the tabs 196 or thestrips 188 to the outer sleeve 198. All three are depicted in a singlesleeve 198 merely for convenience, it being understood that in an actualconstruction, one or more of the attachment methods could be employedfor all of the strips 188 and tabs 196 in a single connector.

[0092] The different attachment methods share a common feature in thatthe tabs 196 or end portions of the strips 188 are fixedly secured tothe sleeve 198 by welds. Since the weld cannot increase the thickness ofthe tab 196 or strip 188, a slight depression or aperture 200 can beformed at the end portion of the tabs 196 or strips 188 at the locationof each weld.

[0093] Thus, according to one aspect, the tabs 196 are folded over thefirst end 194 of the sleeve 198 as in the above described embodiments ofthe invention and then welded to the outer surface of the sleeve 198.Alternately, the tabs 196 can be shortened so as to define a portion 202which has a length only foldable over the first end 194 of the sleeve198.

[0094] According to another aspect of the present invention, the strips188 are formed without any tabs 196 such that the strips 188 terminatein an end 204 within the bore in the sleeve 198 adjacent to the firstend 194 of the sleeve 198.

[0095] Regardless of which construction technique is employed, the endresult is that the strips 188 are maintained in parallel at the firstend 194 of the sleeve 198 and fixedly secured thereto after the freelymovable end portions of the strips 188 at the first end 194 of thesleeve 198 have been rotated the desired amount as in the constructionmethods described above.

[0096] The following description will encompass several differentaspects of an external grid anchor used to fixedly mount one end of thebarrel terminal 80 in a fixed position relative to the barrel terminalbody 62 after the hyperbolic angular offset is applied to the strips 86of the barrel terminal 80 which is only partially illustrated in thefollowing figures.

[0097] As shown in FIG. 10, in one aspect, the external end 96 of thebarrel terminal body 62 is flared outward in an annular flange. The tabs88 at the external end of the barrel terminal 80 are either pre-bent orbent radially outward after the barrel terminal 80 is inserted into thebore 68 in the barrel terminal body 62. The radially disposed tabs 88are fixedly secured to the exterior surface of the flange 96 by suitablemeans, such as by welding. Although low temperature brazing or solderingcould also be employed to fixedly secure the tabs 88 to the flange 96,either ultrasonic or impulse (capacitor-discharge) welding processes maybe better suited for the typical beryllium-copper construction of thegrid of the barrel terminal 80 since these processes generate onlymomentary, localized heating which is confined to the touching surfacesof the tabs 88 and the flange 96 thereby resulting in little adverseeffect on the metal properties of the remainder of the grid or thebarrel terminal 80.

[0098] The external grid anchor shown in FIG. 11 is similar to theexternal grid anchor described above and shown in FIG. 10, except thatthe external end of the barrel terminal body 62 does not include theradially extending flange 96. Rather, the external end 98 of the barrelterminal body 62 is merely an axial end of the body sidewall. The tabs88 are still radially outwardly bent or pre-formed so as to wrap aroundand engage the external end 98. The tabs 88 are then fixed to the end 98by welding as described above. Dimples, not shown, are formed on thefacing surface of one of the tabs 88 or the end of the body 62 forforming the weld.

[0099] In the aspect of the external grid anchor shown in FIG. 12, theoverall length of the barrel terminal 80 is such that the tabs 88 ormerely the ends of the strips 86 forming the grid of the barrel terminal80 are angularly disposed in a pre-stressed shape to exert a radiallyoutward contact force against an inner surface 116 adjacent the innersurface of the end 102 of the barrel terminal body 62. The tabs 88 arefixed in place after the angular offset is formed between the ends ofthe grid strips in the barrel terminal 80 by suitable welding processes,such as ultrasonic welding, impulse-capacitor-discharge welding orpossibly low-temperature brazing or soldering.

[0100] An internal grid anchor 258 depicted in FIGS. 13 and 14 is usedto anchor or fix the inner end of the barrel terminal in a holder. Theinternal grid anchor 258 requires a terminal body 62 in the form of ahollow cylindrical form made from flat stock which is then formed orbent into a cylindrical configuration with oppositely extending boreportions 68 and 74. In the anchor 258, the barrel terminal 80 has thetabs 90 or ends of the strips 86 disposed generally in line with thestrips 86 and not at any significant inward extending, pre-formed angle.The flattened grid containing the strips 86 or individual wires formingthe strips 86 are secured by an internal grid anchoring techniqueemploying welds shown by reference number 258 at the internal end ofeach strip 86. Welding or joining processes must be selected so that themetal properties of the grid of the barrel terminal 80 or the entireterminal body 62 are not adversely effected by the process heat orpressure. Suitable joining processes can include ultrasonic welding,impulse/capacitor-discharge welding, and low-temperaturebrazing/soldering.

[0101] After the internal ends or tabs 90 of the strips 86 of the barrelterminal 80 have been welded to the inner surface of the terminalhousing 60, the terminal body 62 is formed into the cylindrical shapewith the opposed side edges fixedly joined together, by interlockingmechanical connection, welding, etc.

[0102] In FIGS. 15 and 16, yet another internal grid anchor 262 isdepicted. The internal grid anchor 262 is suited for use with the barrelterminal body 62 described above and shown in FIG. 9. The barrelterminal 80 has the tabs 90 at the ends of the strips 86 pre-formed orbent into an angular, generally perpendicular orientation. The barrelterminal 80 may also be formed of individual strips which are notinitially provided in an integral, web connected, grid configuration.

[0103] The internal grid anchor 262 includes projections or contactpoints 264 formed on an outer surface of each projection 90 facing theinternal wall 70 in the bore 68. The projections 264 are at right anglesto the axis of the bore 68 and are readily accessible to weldingequipment through the bore 68. The common plane array of the projections268 greatly facilitates “gang-welding” of the projections 264 to theinternal wall 70 of the barrel terminal housing 62 as shown by the welds266 in FIG. 16.

[0104] Referring now to FIGS. 26 and 27, there is depicted an electricalbarrel socket 300 constructed in accordance with another method. Thesocket 300 is formed as a cartridge which can be mounted in a useelement, as described above.

[0105] The socket 300 includes a contactor or grid, such as the grid 20described above and shown in FIG. 1. The grid 20, which may initially beformed as a flat blank, is formed or bent into a cylindrical, tubularshape as shown in FIG. 2 and inserted into a cylindrical, concentricouter sleeve 28 as shown in FIG. 3.

[0106] In this aspect of the invention, the tabs 26 projecting from thewebs at each end of the grid 20 are formed with a length to be disposedin a predetermined position with respect to one end 302 of the sleeve28, the outer side end wall 304 of the sleeve 28, or in a wrap aroundconfiguration over the outer end surface 306 of the sleeve 28, all ofwhich are depicted in FIG. 25. Thus, by way of example only, the tabs 26are depicted as having a length which allows each tab 26 to be bentradially outward from the cylindrical, axially extending shape shown inFIG. 3 over and in close proximity or contact with the end wall 304 ofthe sleeve 28. The tabs 26 are fixedly secured to the end wall 304 ofthe sleeve 28 by welding, such as ultrasonic welding, spot welding;impulse-capacitor discharge welding or, possibly, low-temperaturebrazing or soldering.

[0107] In the same manner as shown in FIG. 26, the tabs 26 could also bewelded to the inner surface of the sleeve 28 adjacent the end wall 304or provided with a longer length and wrapped around the end portion 306of the outer surface of the sleeve 28 as shown by reference number 196in FIG. 25 and then welded to the exterior surface 306 of the sleeve 28.

[0108] The angular offset or rotation, as described above, is applied tothe tabs 28 at the other end of the grid 20 before the tabs 26 at theopposite end of the grid 20 are fixedly secured by any of the weldingmethods described above to either the interior end surface, the opposedend wall 305 or the exterior end surface 306 of the sleeve 28.

[0109] The above described socket 300 affords a compact socket in acartridge form which can be mounted in a bore in a use element forreceiving an electrical conductor or pin in a smooth, slide-inconnection. The hyperbolic arrangement of the strips 24 in the grid 20between the opposed webs 22 of the grid 20 assure secure electricalcontact with the inserted conductive member as well as affording a highfriction force resisting conductor or pin pull-out from the socket 300.

[0110] Referring now to FIGS. 28 and 29, there is depicted anotheraspect of an internal or blind end anchor 352 useable in the socketshown in FIG. 15. The anchor 352 is in the form of a conically shaped,annular disc 354 which is preferably formed of a material softer thanthe material used to form the barrel terminal body 62. As shown in FIG.28, the disc 354 has a V-shape formed with opposed first and secondV-shaped walls 356 and 358.

[0111] In this aspect, the tabs 90 are initially pre-bent into anangular or perpendicular shape with respect to the remainder of thestrips 86 so as to seat against the internal wall 70 in the bore 68 inthe barrel terminal body 62. After the barrel terminal 80 has beeninserted into the bore 68, with the tabs 90 disposed adjacent to theinternal wall 70, force, by a punch or other tool member inserted intothe bore 68 internally of the strips 86 of the barrel terminal 80, isapplied in the direction of the arrow in FIG. 29 against the firstsurface 356 of the disc 354 to deform the V-shaped disc 354 into agenerally flat or planar shape shown in FIG. 29. This displaces thesofter material of the disc 354 radially and axially outward away fromthe direction of the applied forced so as to compressively trap the tabs90 on the barrel terminal 80 against the inner wall 70 and the adjacentsidewalls of the bore 68 as shown in FIG. 28.

[0112] In FIGS. 30 and 31, a different internal grid anchor 368 isdepicted. In this aspect of the invention, the internal grid anchor 168includes a generally flat washer 370 having an central bore or aperture372 formed therethrough. The aperture 372 in the washer 370 receives anib or projection 374 which is an integral extension of a solid portionof the barrel terminal body 62 which forms the internal wall 70. The nib374 initially has a generally cylindrical shape and a diameter to allowthe nib 374 to extend easily through the central bore 372 in the washer370.

[0113] During the assembly process, after the barrel terminal 80 hasbeen inserted into the bore 68 in the barrel terminal body 62, with orwithout the tabs 90 on the strips 86 of the barrel terminal 80 beingangularly bent with respect to the remainder of the strips 86, a forceis applied in the direction of the arrow in FIG. 36 to the outer surfaceof the nib 374. This results in outward expansion of the material of thenib 374 causing the nib 374 to mushroom radially outward thereby forcingthe perimeter of the washer 370 to expand locking the adjacent portionsof the tabs 90 or strips 86 to the walls of the barrel terminal body 62as shown in FIG. 31. This radially outward mushrooming of the nib 374also causes a radial expansion of the outer end surface of the nib 374over an adjacent portion of the washer 370 adjacent to the bore 372 inthe washer 370. This interference prevents linear pull-out of the washer370 and the barrel terminal 80 from the body 62.

[0114] Another aspect of an internal grid anchor 396 is depicted inFIGS. 32 and 32. The anchor 396 is usable in connector applicationswhere the material forming the barrel terminal body 62 is not malleableenough to enable deformation of the integrally formed nib, such as nib368.

[0115] In this application, a bore 398 is formed through the centralsolid portion of the terminal housing 60 between the internal wall 70and the opposed internal wall 76. A cylindrical rivet-like body 400 hasan enlarged end flange 202 at one end. The body 400 is inserted throughthe bore 398 with the enlarged end flange 402 disposed adjacent to theinternal wall 76 in the bore 74 in the terminal housing 60. The otherend of the body 400 has a counterbore 404 which extends axially awayfrom the internal wall 70 beyond the tabs 90 on the ends of the strips86 of the barrel terminal 80. A compressive force applied by a punch ordie, not shown, in the direction of the arrow in FIG. 33 in thecounterbore 404 deforms one end of the malleable body 400, while theother flange 402 end of the body 400 is held in a fixed position againstthe inner wall 76. This results in deformation of the end of the body400 radially outward into a rivet-like mechanical interlock connectionbetween the tabs 90 and the adjacent ends of the strips 86 of the barrelterminal 80 locking the barrel terminal 80 in contact with the innerwall of the barrel terminal body 62.

[0116] An internal grid anchor 440 shown in FIGS. 34 and 35 includes anannular, generally flat disc or washer 442 inserted into the bore 68 inthe barrel terminal body 62. An external compressive, circumferentialforce shown by the arrows in FIG. 35 is applied to the exterior surfaceof the barrel terminal body 62 generally at the location of the washer442. These forces result in a depression 444 which results indeformation of the metal forming the sidewall of the barrel terminalbody 62 to mechanically interlock the tabs 90 and/or ends of the stripsof the barrel terminal 80 with the washer 442 and the sidewall of thebore 68 of the barrel terminal body 62.

[0117] In FIG. 36, a rivet-type joining technique is employed to fixedlysecure an anchor 460 to the inner wall 76 of the bore 74. However, inthis aspect of the invention, the contact wires 462 are joined or weldedto the opposite or outer surface of an annular disc 464. In this aspect,the contact wires 462 are not wrapped around the periphery of theannular disc 464; but could be.

[0118] Referring now to FIGS. 37-40, there is depicted an electricalconnector 500 constructed in accordance with the teachings of thepresent invention. Generally, the electrical connector 500 includes aholder 502, an electrically conductive barrel socket 504, a pull-outforce resistance means 506 and a conductive end form, such as a 508. Thebarrel socket 504 is depicted, by example only, as being constructedaccording to the method and structure shown in FIGS. 1-8 and describedabove. It will be understood that the barrel socket 504 may take otherforms, such as any of the barrel socket constructions described aboveand shown in FIGS. 1-38.

[0119] As shown in FIGS. 37-40, the barrel socket 504 is mounted in theholder 502 in a bore 510 extending from a first end 512 of the holder502. The barrel socket 504 is preferably fixedly and non-rotatablymounted in the bore 510 in the holder 502 by suitable means, such as bya press or interference fit created by inward tapering sidewalls formingthe bore 510. A shoulder 514 is formed internally of the holder 502 atone end of the bore 510 and functions as a seat to limit the insertionof the barrel socket 504 into the bore 510.

[0120] The opposed end 516 of the holder 502 may take a variety ofshapes depending on the particular application in which the electricalconnector 500 is employed. Thus, it will be understood that theillustrated generally tubular shape for the holder 502 is by way ofexample only as the end 516 of the holder 502 may be part of a useelement.

[0121] In the depicted structure, a bore 518 extends axially from theend 516 and is depicted as being in communication with the bore 510through an intermediate, reduced diameter intermediate bore 520. Thebores 518 and 520 may be sized to slidably receive a pin which isinserted into the inner end of the barrel socket 504 mounted in the bore510 of the holder 502. Alternately, at least the bore 518 may receivethe stranded or bare ends of a stranded electrical conductor which arestationarily fixed in the holder 502 by solder, crimping, or otherconventional electrical joining techniques.

[0122] Similarly, the conductive end form 508 may take a variety ofshapes depending upon the particular application of the electricalconnector 500. Thus, the end form 508 is shown in FIGS. 38-40, by way ofexample only, as having an elongated pin 524 extending from a first end526 to an intermediate shoulder 528. A radially enlarged flange 530projects radially outward from an enlarged surface 532 extending fromthe periphery of the shoulder 528. The surface 532 extends to an opposedsecond end 534 of the end form 508. A bore 536 extends axially inwardfrom the second end 534 and is adapted for receiving a separate pin, orthe bare ends of a stranded conductor which are fixedly secured in thebore 536 by solder, crimping and/or any other electrical connectorjoining technique.

[0123] The end form 508 is devised for sliding insertion into the bore540 of the barrel socket 504 through a first end 542 of the barrelsocket 504. The length of the first end portion 524 of the end form 508is selected to provide a suitable insertion distance into the bore 540in the barrel socket 504. If necessary, this insertion distance maylimited by the shoulder 528 contacting the first end 542 of the barrelsocket 504 as most closely shown in FIG. 38.

[0124] The pull-out force resistance control means 506 according to thepresent invention includes a stop means 550 which has a central bore 552having an inner diameter sized to slidably allow insertion of the pin524 of the end form 508 therethrough. The stop means or member 550 isformed of a flexible material or of a small thinness to permit flexureof an inner edge surrounding the bore 552.

[0125] Means 454 are provided for spacing the stop member 550 from thefirst end 542 of the barrel socket 504 as shown in FIGS. 38-40. Thespacer means 554 may be in the form of a generally planar or flat washerhaving a central bore 556 of an inner diameter larger than the innerdiameter of the bore 552 in the stop member 550 and larger than the bore540 in the barrel socket 504. Means are provided for fixing the stopmeans 550 and the spacer means 554 in an axial position relative to thefirst end 542 of the barrel socket 504.

[0126] A means for fixing the stop member 550 and the spacer 554 withrespect to the barrel socket 504 denoted by reference number 560 is inthe form of an end cap having a sidewall 562 and an end wall 564 whichdefine a hollow interior chamber 566. A bore 568 is formed in the endwall 564 and has an inner diameter sized to slidably allow insertion ofthe pin 524 of the end form 508 therethrough. The inner diameter of thebore 568 may be the same as the inner diameter of the bore 552 in thestop means 550.

[0127] The sidewall 562 of the end cap 560 is sized for fixed mountingover the outer sleeve 570 or exposed ends of the grid of the barrelsocket 504, depending upon the specific construction or structure of thebarrel socket 504 as described above and shown in FIGS. 1-37. In oneaspect of the invention, the dimensional relationship between the outerperipheral surface of the barrel socket 504 at the first end 542 and theinner surface 572 of the open ended interior chamber 546 in the end cap560 is sized for an interference or press-fit. Alternately, the end cap560 may be fixedly secured to the barrel socket 504 by mechanicalfasteners, solder, etc.

[0128] As shown in FIG. 40, with a spacer 554, the stop member 550 inthe end cap 560 fixedly secured over the first end 542 of the barrelsocket 504, either before or after the barrel socket 504 is mounted inthe holder 502, the larger interior diameter of the bore 556 in thespacer 554 forms an annular recess 580 between the end 542 of the barrelsocket 504 in the adjacent inner diameter edge 582 of the stop member550.

[0129] The recess 580 receives a projection means 584 formed or carriedon the pin 524 as shown in FIGS. 38-40. The projection means 584 maycomprise a single enlarged projection extending over at least a portionof the circumference of the pin 524, a plurality of coplanar,circumferentially spaced, discrete projections 584, or, in anillustrated aspect of the invention, a single, continuous annular ringextending radially outward from the exterior surface of the end portion524 of the pin 524 to an outer edge 586 disposed at a given diameter.The diameter of the outer edge 586 of the projection 584 is sized topass freely through the inner diameter of the bore 568 in the end cap564 and interfere with the inner edge portion 582 of the stop member550. However, the insertion force, which may be from ten to twentypounds, for example, will be sufficient to cause axially inward flexingof the inner edge portion 582 of the stop member 550 in a directiontoward the end 542 of the barrel socket 504 to allow the projection 584to clear the inner diameter of the bore 552 in the stop member 550 andpass into the recess 580 formed internally within the bore 456 of thespacer 550. After the projection 584 clears the inner edge portion 582,the inner edge portion 582 returns to a planar shape.

[0130] Further insertion of the pin 508 into the barrel socket 504 islimited by engagement of the projection 584 with the end 542 of thebarrel socket 504 which cannot be radially expanded due to the end cap560 or the outer sleeve 570. In this manner, the pin 524 is fixedlylatched in the barrel socket 504 to complete the electrical connectionbetween the pin 524 and the holder 502.

[0131] However, the pin 524 can be forcibly removed from the barrelsocket 504 in the holder 502, but at a substantially high pull-out forcewhich acts to forcibly retain the pin 524 in the barrel socket 504 undernormal loads. For example, with an electrical connector 500 constructedin accordance with the present invention with the components sized toprovide a ten to twenty pound insertion force, the pull-out force may beabout fifty pounds. During any pull-out event tending to disengage thepin 524 from the holder 502, which pull-out force may be provided on theholder 502 or the pin 524, or both the projection 584 on the pin 524will be forced into engagement with the inner edge surface 582 of thestop member 550. However, the inner edge surface 582 is prevented fromflexing in an axially outward direction away from the end 542 of thebarrel socket 504 by the adjacent inner edge of the end wall 564 of theend cap 560 surrounding the bore 568 in the end cap 560. This adjacencyof the two inner edge portions of the end wall 564 of the end cap 560and the inner edge 582 of the stop member 550 retains the inner edge 582of the stop member 550 in a planar position resisting passage of theprojection 584 there past until a sufficient amount of pull-out force isexerted to deform and bend the inner edge portion 582 of the stop member550 axially outward at least partially into the bore 568 in the end wall564 of the end cap 560 until the projection 584 on the pin 524 can passthrough the bore 568 in the end cap 560 to provide disengagement of thepin 508 from the holder 502.

[0132] The amount of pull-out force resistance provided by theelectrical connector 500 can be varied to suit the requirements of aparticular application. The pull-out force resistance can be varied bymodifying the strength of the material used to form the stop member 550to thereby provide greater or lesser amounts of flexure capability forthe inner edge 582 of the stop member 550. The material forming theprojection 584 on the pin 508 can also be varied in strength to providegreater or lesser amounts of force exerted on the stop member 550 beforedeforming.

[0133] In summary, there has been disclosed a unique electricalconnector employing a radially resilient electrical barrel socket whichhas increased pull-out resistance for an electrically conductive endform inserted into the barrel socket over previously devised radiallyresilient barrel sockets. The increased pull-out force resistance isprovided without modification to the structure of the barrel socket andcan be easily varied to suit the pull-out force requirements of aparticular application.

What is claimed is:
 1. An electrical connector comprising: a radiallyresilient barrel socket having a bore with a first inner diameterextending from a first end; a stop member having a bore with a secondinner diameter, the second inner diameter being at least as large as thefirst diameter of the bore in the barrel socket; means for spacing thestop member from the one end of the barrel socket and defining a recessbetween the second inner diameter of the bore in the stop member and theone end of the barrel socket, the recess having a third inner diametergreater than the second inner diameter of the bore in the stop memberand the first inner diameter of the bore in the barrel socket; means forfixing the stop member and the spacing means with respect to the one endof the barrel socket; an electrically conductive member having an endpin insertable through the fixing means, the spacing means, and the stopmember into the bore in the barrel socket; and at least one projectioncarried on the pin, the at least one projection insertable through theinner diameter of a bore formed in the fixing means into the recessdefined by the spacing means, an inner edge of the bore in the fixingmeans and an inner edge of the bore in the spacing means resistingmovement of the at least one projection on the pin axially outward fromthe one end of the barrel socket up to a predetermined pull-out force.2. The electrical connector of claim 1 wherein the spacing meanscomprises: a spacer member having a bore with a third inner diameter,the third inner diameter being larger than the second inner diameter ofthe stop member and the first inner diameter of the bore in the barrelsocket, the recess formed radially inward of the third inner diameter ofthe spacer member.
 3. The electrical connector of claim 2 wherein thespacer member comprises: a flat washer.
 4. The electrical connector ofclaim 1 wherein the fixing means comprises: an end cap having a sidewall and an end wall, a bore formed in the end wall having an innerdiameter sized to allow free passage of the at least one projectiontherethrough, an inner edge of the end wall surrounding the innerdiameter of the bore disposed in substantial engagement with an inneredge of the spacing means surrounding the bore in the spacing means toresist axially outward movement of the inner edge of the spacing meanswhen the pin is moved in an axially outward direction relative to theone end of the barrel socket.
 5. The electrical connector of claim 4wherein the spacing means comprises: a spacer member having a bore witha third inner diameter, the third inner diameter being larger than thesecond inner diameter of the stop member and the first inner diameter ofthe bore in the barrel socket, the recess formed radially inward of thethird inner diameter of the spacer member.
 6. The electrical connectorof claim 4 wherein: the cap is mounted over the one end of the barrelsocket.
 7. The electrical connector of claim 6 wherein: the cap isfixedly mounted on the barrel socket.
 8. The electrical connector ofclaim 7 wherein: the end cap is press-fit on the barrel socket.
 9. Theelectrical connector of claim 1 wherein the at least one projectioncomprises: a plurality of circumferentially spaced, discrete projectionscarried on the pin.
 10. The electrical connector of claim 1 wherein theat least one projection comprises: a single continuous annularprojection carried on the pin.
 11. The electrical connector of claim 1wherein: the outer diameter of the at least one projection is greaterthan the second inner diameter of the bore in the spacing means.
 12. Theelectrical connector of claim 1 further comprising: the spacing meanshaving an inner diameter portion surrounding the bore in the spacingmeans capable of axial flexure on insertion of the at least oneprojection on the pin therethrough to allow passage of the at least oneprojection into the recess; and the fixing means and the spacing meansresisting flexure of the inner diameter portion of the spacing means inan axial direction away from the one end of the barrel socket in adirection tending to separate the pin from the barrel socket.
 13. Anelectrical connector comprising: a radially resilient barrel sockethaving a bore with a first inner diameter extending from a first end; astop member having a bore with a second inner diameter, the second innerdiameter being at least as large as the first diameter of the bore inthe barrel socket; means for spacing the stop member from the one end ofthe barrel socket and defining a recess between the second innerdiameter of the bore in the stop member and the one end of the barrelsocket, the recess having a third inner diameter greater than the secondinner diameter of the bore in the stop member and the first innerdiameter of the bore in the barrel socket; means for fixing the stopmember and the spacing means with respect to the one end of the barrelsocket; an electrically conductive member having an end pin insertablethrough the fixing means, the spacing means, and the stop member intothe bore in the barrel socket; and a single annular projection carriedon the pin, the projection insertable through the inner diameter of abore formed in the fixing means into the recess defined by the spacingmeans, an inner edge of the bore in the fixing means and an inner edgeof the bore in the spacing means resisting movement of the projection onthe pin axially outward from the one end of the barrel socket up to apredetermined pull-out force.
 14. The electrical connector of claim 13wherein the spacing means comprises: a spacer member having a bore witha third inner diameter, the third inner diameter being larger than thesecond inner diameter of the stop member and the first inner diameter ofthe bore in the barrel socket, the recess formed radially inward of thethird inner diameter of the spacer member.
 15. The electrical connectorof claim 13 wherein the fixing means comprises: an end cap having a sidewall and an end wall, a bore formed in the end wall having an innerdiameter sized to allow free passage of the at least one projectiontherethrough, an inner edge of the end wall surrounding the innerdiameter of the bore disposed in substantial engagement with an inneredge of the spacing means surrounding the bore in the spacing means toresist axially outward movement of the inner edge of the spacing meanswhen the pin is moved in an axially outward direction relative to theone end of the barrel socket.
 16. The electrical connector of claim 15wherein: the end cap is fixedly mounted on the barrel socket.
 17. Anelectrical connector comprising: a radially resilient barrel sockethaving a bore with a first inner diameter extending from a first end; astop member having a bore with a second inner diameter, the second innerdiameter being at least as large as the first diameter of the bore inthe barrel socket; a spacer member spacing the stop member from the oneend of the barrel socket and defining a recess between the second innerdiameter of the bore in the stop member and the one end of the barrelsocket, the recess having a third inner diameter greater than the secondinner diameter and the one end of the bore in the barrel socket, thespacer member having a bore with a third inner diameter, the third innerdiameter being larger than the second inner diameter of the stop memberand the first inner diameter.of the bore in the barrel socket, therecess formed radially inward of the third inner diameter of the spacermember; means for fixing the stop member and the spacer member withrespect to the one end of the barrel socket, the fixing means includingan end cap having a side wall and an end wall, a bore formed in the endwall having an inner diameter sized to allow free passage of the atleast one projection therethrough, an inner edge of the end wallsurrounding the inner diameter of the bore disposed in substantialengagement with an inner edge of the spacer member surrounding the borein the spacing means to resist axially outward movement of the inneredge of the spacing means when the pin is moved in an axially outwarddirection relative to the one end of the barrel socket; an electricallyconductive member having an end pin insertable through the fixing means,the spacing means, and the stop member into the bore in the barrelsocket; and a projection carried on the pin, the projection insertablethrough the inner diameter of a bore formed in the fixing means into therecess defined by the spacing means, an inner edge of the bore in thefixing means and an inner edge of the bore in the spacing meansresisting movement of the projection on the pin axially outward from theone end of the barrel socket up to a predetermined pull-out force.